I find I typically put it into Sport as soon as I start moving. The difference is pretty dramatic.

I've had the car 3 days so still breaking it in. Been in EcoPro mode for about 75% of the time - mostly just to play around and see how high I could get my mpg during my commute to work. Other portion is in Comfort with just a few fun minutes in Sport. It's hard not to rev past 4500 in Sport mode so I'm trying to stay away from it during break in. Can't wait to unleash the beast though!!